//
//  ViewController.m
//  CoreData082519
//
//  Created by Golibyo on 15/11/20.
//  Copyright © 2015年 changshuhua. All rights reserved.
//

#import "ViewController.h"
#import "CoreDataManager.h"
#import "Student.h"
@interface ViewController ()
@property(nonatomic, strong)CoreDataManager *manager;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.manager = [CoreDataManager defaults];
    [self.manager applicationDocumentsDirectory];
    NSLog(@"url========%@", [self.manager applicationDocumentsDirectory]);
    
    
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
- (IBAction)delete:(id)sender {
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Student" inManagedObjectContext:self.manager.managedObjectContext];
    [fetchRequest setEntity:entity];
    // Specify criteria for filtering which objects to fetch
    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"sex", @"%@"], @"?"];
    [fetchRequest setPredicate:predicate];
    // Specify how the fetched objects should be sorted
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"sex"
                                                                   ascending:YES];
    [fetchRequest setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    
    NSError *error = nil;
    NSArray *fetchedObjects = [self.manager.managedObjectContext executeFetchRequest:fetchRequest error:&error];
    for (Student *temp in fetchedObjects) {
        [self.manager.managedObjectContext deleteObject:temp];
    }
    [self.manager saveContext];
}
- (IBAction)update:(id)sender {
    //    获取查询的请求,相当于数据库的查询语句
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Student"];
    //    添加约束  谓词
    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"name", @"%@"], @"成精"];
    //    添加约束条件
    request.predicate = predicate;
    //    通过某个key给数组排序
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];
    [request setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    NSError *error;
    NSArray *array = [self.manager.managedObjectContext executeFetchRequest:request error:&error];
    Student *stu = [array lastObject];
    stu.sex = @"女";
    
    [self.manager saveContext];
}

//查找
- (IBAction)select:(id)sender {
//    获取查询的请求,相当于数据库的查询语句
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Student"];
//    添加约束  谓词
    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"name", @"%@"], @"成精"];
//    添加约束条件
    request.predicate = predicate;
//    通过某个key给数组排序
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];
    [request setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    NSError *error;
    NSArray *array = [self.manager.managedObjectContext executeFetchRequest:request error:&error];
    NSLog(@"%ld", array.count);
    
}
// coredata添加方法
- (IBAction)add:(id)sender {
    // 创建实体描述
    // 参数1:描述的实体
    // 参数2:数据管理器
    
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Student" inManagedObjectContext:self.manager.managedObjectContext];
    // 创建实体
    // 参数1:实体描述
    // 参数2:数据管理器
    Student *stu = [[Student alloc] initWithEntity:entity insertIntoManagedObjectContext:self.manager.managedObjectContext];
    stu.name = @"成精";
    stu.age = @100;
    stu.sex = @"?";
    stu.hobby = @"haha";
    stu.number = @1563;
    stu.key = @"5165156";
    [self.manager saveContext];
    
}

@end
